Relationships between training load, sleep duration, and daily wellbeing and recovery measures in youth athletes

Purpose: To assess the relationships between training load, sleep duration and three daily wellbeing, recovery and fatigue measures in youth athletes. Methods: Fifty-two youth athletes completed three maximal countermovement jumps (CMJ), a daily wellbeing questionnaire (DWB), the Perceived Recovery Status scale (PRS), and provided details on their previous day's training loads (training) and self-reported sleep duration (sleep) on four weekdays over a seven week period. Partial correlations, linear mixed models and magnitude-based inferences were used to assess the relationships between the predictor variables (training; sleep) and the dependent variables (CMJ; DWB; PRS). Results: There was no relationship between CMJ and training (r=-0.09; ±0.06) or sleep (r=0.01; ±0.06). The DWB was correlated with sleep (r=0.28; ±0.05, small), but not training (r=-0.05; ±0.06). The PRS was correlated with training (r=-0.23; ±0.05, small), but not sleep (r=0.12; ±0.06). The DWB was sensitive to low sleep(d=-0.33; ±0.11) relative to moderate, PRS was sensitive to high (d=-0.36; ±0.11) and low (d=0.29; ±0.17) training relative to moderate. Conclusions: The PRS is a simple tool to monitor the training response, but DWB may provide a greater understanding of the athlete's overall wellbeing. The CMJ was not associated with the training or sleep response in this population

The within-participant Correlation between s-RPE and Heart Rate in Youth Sport

The monitoring of training load is important to ensure athletes are adapting optimally to a training stimulus. Before quanti ca- tion of training load can take place, coaches must be con dent that the tools available are accurate. We aimed to quantify the within-participant correlation between the session rating of perceived exertion (s-RPE) and summated heart rate zone (sHRz) methods of monitoring internal training load. Training load (s-RPE and heart rate) data were collected for rugby, soc- cer and eld hockey eld-based training sessions over a 14- week in-season period. A total of 397 sessions were monitored (rugby n = 170, soccer n = 114 and eld hockey n = 113). With- in-subject correlations between s-RPE and sHRz were quanti- ed for each sport using a general linear model. Large correla- tions between s-RPE and the sHRz method were found for rugby (r = 0.68; 95 % CI 0.59–0.75) and eld hockey (r = 0.60; 95 % CI 0.47–0.71) with a very large correlation found for soccer (r = 0.72; 95 % CI 0.62–0.80). No signi cant di erences were found between the correlations for each sport. The very large and large correlations found between s-RPE and the sHRz meth- ods support the use of s-RPE in quantifying internal training load in youth sport

Augmentation of chimerism in whole organ recipients by simultaneous infusion of donor bone marrow cells

We had previously demonstrated the persistence of donor leukocytes in the peripheral blood and tissues of long-surviving kidneyl and live2-4 recipients who had stable graft function many years after transplantation.1-6 Donor cell chimerism has since been noted by other investigators in recipients of heart,7 liver,8 kidney,9 and lungl0 transplants. In an attempt to augment chimerism, and thereby facilitate graft function, we initiated a prospective trial to enhance this phenomenon by infusing 3 × l0(8)/kg unaltered donor bone marrow cells perioperatively into an unmodified recipient of whole organ from the same donor. Additionally, 53 recipients of whole organ alone were monitored as controls. Reported herein are the first 20 of 64 study patients and 33 of 53 control patients who are more than 120 days posttransplantation